Chemische Werke Huels Aktiengesellschaft

Chemische Werke Huls Aktiengesellschaft

Wilhelm Knepper

Dieter J Mueller

Dieter J Muller

Gerhard Sticken

Heinz Rassaerts

An improved process for the conversion of allyl and methallyl chloride to sodium allyl and methallyl sulfonate, respectively, by reaction with aqueous sodium sulfite which comprises conducting the reaction at 33.degree.-70.degree. C. and 33.degree.-80.degree. C., respectively, while maintaining the pH at 7-11 throughout the reaction.

Preparation of sodium allyl and methallyl sulfonate

Reaction of methallyl chloride (MAC) containing isocrotyl chloride (ICC) with aqueous sodium sulfite solution in an emulsion at 30.degree.-80.degree. C. and pH 7-11, maintained constant during the reaction by metered addition of sodium hydroxide solution is done in a two-step process, in the first step of which a mixture enriched in ICC and depleted in MAC from a preceding reaction batch and/or the second reaction step as excess organic residual phase, is reacted with an excess of concentrated sulfite solution until the MAC has been practically completely consumed; and, in the second step of which the reaction solution remaining after separating the unreacted ICC by distillation is reacted with a technical MAC/ICC mixture containing an excess of MAC until sulfite has been practically completely consumed. Thereafter, the excess organic residual phase is recycled to the first step after distillative separation. The MAC is preferably added in 10-40% excess in the second step.

Process for the preparation of sodium methallyl sulfonate

A process for preparing trichloroethylene by chlorinating 1,2-dichloroethane in the liquid phase in the presence of ethylene followed by pyrolytic chlorination or dehydrochlorination of the reaction product. The 1,2-dichloroethane is chlorinated in the liquid phase in a bubble column reactor in the presence of 1 - 10 mole percent of ethylene with a chlorine/1.2-dichloroethane feed ratio of about 0.7 - 1.4/1, a temperature of about 40.degree. to 150.degree.C with superficial velocities exceeding 8 cm/sec. and gas dwell times of about 0.3 to 10 seconds. The chlorinated product is reacted in the gas phase with recirculated tetrachloroethanes and about 20 - 70 moles of chlorine per 100 moles of chlorinated hydrocarbons at temperatures of about 380.degree. to 500.degree.C and dwell times of about 20 to 30 seconds. This gas phase reaction product is separated by distillation into a low-boiling fraction containing predominantly dichloroethylenes and a high boiling fraction containing predominantly trichloroethylene. The low boiling fraction is reacted in the liquid phase with equimolar amounts of chlorine at temperatures of about 60.degree. - 150.degree.C to obtain the tetrachloroethanes that are recirculated. The high boiling fraction is then separated by distillation into the trichloroethylene product and higher boiling point side products.

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Marl, Germany

Wilhelm Knepper